In a classifier whose classification accuracy is maintained without frequently collecting labeled learning data, a learning unit learns a classification criterion of a classifier at each time point in the past until the present and learns a time series change of the classification criterion by using data for learning to which a label is given and that is collected until the present. A classifier creating unit predicts a classification criterion of a future classifier and creates a classifier that outputs a label representing an attribute of input data by using the learned classification criterion and time series change.